User devices, such as wireless telephones may wirelessly connect, or “attach,” to a wireless network via a base station. The base station may provide multiple carriers, to which the user devices may attach. As used herein, a particular “carrier” may refer to a particular radio access technology, a particular frequency band, and/or a particular set of frequencies within a frequency band. The frequency bands, provided by the base station, may include licensed frequency bands. “Licensed” frequency bands may be frequency bands which have been licensed, by an authoritative entity, such as a government agency, for exclusive use by a particular wireless network service provider. In some situations, the base station may also provide service according to one or more shared frequency bands. “Shared” frequency bands may be frequency bands that have been authorized (e.g., by an authoritative entity) for use by multiple wireless network service providers.